Rotary cylinder for heat treatment of fabrics or the like continuous materials



July 1, 1969 M. DURAND 3,452,967- ROTARY CYLINDER FOR HEAT TREATMENT OFFABRICS OR THE LIKE CONTINUOUS MATERIALS Filed Sept. 20, 1967 FiG.1

5;; :Iiiii EL-11 3 6 T r 1 I "U55: 19 3f I'U I 5U L 1 4 United StatesPatent US. Cl. 2636 7 Claims ABSTRACT OF THE DISCLOSURE A rotarycylinder for thermal treatment comprises outer and inner annular shellssecured to a pair of spaced discs and defining an annular chamberadapted for filling with a thermally conductive fluid, there beinghelical blades in the chamber for stirring the fluid. One end of atubular fire chamber with a burner thereat is secured to one of thediscs and the opposite end of the fire chamber is open and disposed witha tubular member within the inner shell to define an S-shaped flow pathfor the combustion gases from the interior of the fire chamber to adischarge outlet in the other disc.

The present invention relates to an improved rotary cylinder for heattreatment of fabrics or the like continuous materials.

Rotary heating cylinders are commonly used for heat treating saidmaterials, for instance, for fixing, drying, or polymerizing the liquidssoaking a fabric after the latter is impregnated.

Such cylinders may be heated either by means of electric resistors, orby fluids circulated in a coil by a pump, or else by one or more oil orgas burners or the like.

Differences in temperature of the order of 10 C. are to be noted on theouter surfaces of the rotary cylinders directly heated by an innerburner which are presently used, which differences disturb to a certainextent the treatment performed by said cylinders.

The object of the present invention is to obviate said drawback. To thisend, the invention relates to an internally heated rotary cylinder forheat treatment of fabrics or the like continuous materials, of the typeheated by a burner and constituted by two discs to which two cylindricalshells are secured, which shells are coaxial and different in diameterand form an annular chamber filled with a thermally conductive fluid,said cylinder including a tubular fire-chamber which is heated toredness by the above-mentioned burner and opens into a diffusing shellnear the bottom of the latter, said diffusing shell being arranged insaid cylinder in a way such that the gases produced by the combustionfollow an S-like path during which they become still hotter as theycontact said diffusing shell before flowing along the inner surface ofthe annular chamber, the latter being provided internally with helicalblades which stir the thermal fluid contained in said chamber, uponrotation of the cylinder, whereby the heat is distributed on the outercylindrical shell and a constant temperature is obtained at the outersurface of the latter, throughout the length thereof.

According to a preferred embodiment of the invention, the discs of saidcylinder are integral each with a hollow shaft, the burner passingthrough one of said shafts, while the other shaft is connected with asmoke exhauster, the disc through which the burner passes being integralwith the tubular fire-chamber.

Furthermore, the helical blades have a winding direc tion which is afunction of the direction in which the cylinder rotates, and they aredisposed on the smaller cylindrical shell of the annular chamber of thecylinder.

Said helical blades are advantageously perforated, to ensure a betterstirring of the thermal fluid during the rotation of the cylinder.

The invention will now be described in further detail, with reference tothe appended diagrammatic drawing, which illustrates, by way ofnon-limiting example, an embodiment of the rotary cylinder of theinvention. In said drawing:

FIGURE 1 shows a longitudinal section of said cylinder, along line 11 ofFIGURE 2; and

FIGURE 2 is an elevational end view of same, in partial cross-sectionalong line 22 of FIGURE 1.

The cylinder of the invention includes two discs, 2, 3, each of which isintegral with a hollow shaft, 4, 5, respectively.

A burner 6 passes through the hollow shaft 4, while the hollow shaft 5is connected with a smoke exhauster (not shown).

A ring 7 is bolted on each disc 2, 3. The two rings 7 are integral withtwo concentric cylindrical shells, to wit, a larger shell 8, the outersurface 9 of which constitutes the working part of the cylinder, and asmaller shell 10, the inner surface of which constitutes one of thesurfaces of the path of the gases.

Said two cylindrical shells 8, 10, the ends of which are welded to therings 7, form a fluid-tight annular chamber 13 containing a thermallyconductive fluid, the boiling point of which is considerably higher thanthe temperature obtained when heating the cylinder.

In a known way, the chamber 13 is not completely filled with fluid, soas to allow the latter to expand freely when the temperature rises.

According to the invention, helical blades 14 are welded to thecylindrical shell 10, inside the annular chamber 13, so as to produce astirring of the fluid when the cylinder is rotated, which stirring upensures the distribution of said fluid inside said chamber 13 and,consequently, a uniform heat distribution over the cylindrical shell 8,in order that the temperature of the surface 9 of said shell may be thesame throughout the length thereof.

Of course, the winding direction of the blades 14 is determined as afunction of the direction in which the cylinder rotates. Furthermore, asshown in FIGURE 1, the flame from the burner '6 is sent forth into atubular fire-chamber 15, which is made of refractory steel and welded tothe inner surface of the disc 2. Said tubular fire-chamber 15 opens inturn near the dished bottom of a second tube 17 welded to angle members18, the latter being in turn welded tothe inner wall 12 of the smallercylindrical shell 10. Said tube 17 constitutes a diffusing shell.

The fire-chamber 15, the tube or shell 17, and the wall 12, which aredisposed on the same axis and equidistant, form thus an S-shaped pathfor gases, which path as shown by the arrows 19 in FIGURE 1, ensuresthat said gases are heated to a maximum.

As a matter of fact, said gases flow out of the tubular fire-chamber 15,which is heated to redness by the flame of the burner 6, and, afterbeing turned back by the bottom 16, they are guided by the outer surfaceof said fire-chamber, which heats them further, and by the inner surfaceof the diffusing shell 17, until they reach the vicinity of the disc 2,where they are guided by the outer surface of the tube 17 and the innersurface 12 of the smaller cylindrical shell 10, to which they transfer aportion of their heating energy. Said shell 10, heated thus along itsinner surface 12, transmits its heat to the fluid which is in contactwith the outer surface of said shell 10.

Owing to said arrangement. the heating energy generated by the flame ofthe burner is utilized to the utmost, so that, for any given workingtemperature, the working costs of the cylinder of the invention arelower than those of a conventional cylinder.

Furthermore, the temperature of the cylinder of the invention is thesame at all points of the length of its working surface 9, and this istrue whatever the diameter of said cylinder may be, owing to thearrangement of the helical blades 14.

Furthermore, said blades may be perforated, in order to stir the gaseseven more efirciently.

The cylinder of the invention may include pipes 20 welded to the disc 2and passing through the latter to open into the starting chamber for thegases, which chamber is located below the surface 12 of the cylindricalshell 10, which pipes provide for the inlet of additional air to thecylinder.

Furthermore, a sight-hole in the disc 2 enables the combustion of theflame of the burner 6 to be supervised.

What I claim is:

1. A rotary cylinder for thermal treatment comprising a pair of spaceddiscs, outer and inner annular shells secured to said discs and definingan annular chamber adapted for being filled with a thermally conductivefiuid, helical blades supported in said chamber for stirring said fluid,a tubular fire chamber having one end secured to one of said discs andan opposite end which is open and disposed within the inner shell,burner means in said fire chamber in the region of said one disc, meansat the other disc for discharge of combustion gases produced by saidburner, a tubular member mounted within the inner shell and having aclosed end facing said open end of the fire chamber, said tubular memberencircling said fire chamber and having an open end spaced from the discto which the fire chamber is secured, whereby to define an S-shaped flowpath for the combustion gases .4 from the interior of said fire-chamber,then around the exterior thereof and finally around the exterior of thetubular member and to the discharge means.

2. A rotary cylinder as claimed in claim 1 comprising a hollow rotatableshaft secured to each disc and projecting therethrough, said burnermeans extending in one shaft and said means for the discharge of thecombustion gases being coupled to the other shaft.

3. A rotary cylinder as claimed in claim 1, wherein said helical bladesare secured to the inner shell.

4. A rotary cylinder as claimed in claim 3, wherein said helical bladesare perforated.

5. A rotary cylinder as claimed in claim 1, wherein said helical bladeshave a height which is less than the radial height of said annularchamber.

6. A rotary cylinder as claimed in claim 1, wherein said shells arecylindrical and coaxial, and said fire chamber and tubular member arecoaxially mounted within said shells.

7. A rotary cylinder as claimed in claim 1 comprising means forsupplying air through said one disc to the space between the tubularmember and the inner shell.

References Cited UNITED STATES PATENTS 2,362,947 11/ 1944 Sullivan.2,844,887 7/1958 Hornbostel 34-119 2,987,305 6/ 1961 Calhoun. 3,229,7581/1966 Pilnik et al 90 JOHN J. CAMBY, Primary Examiner.

US. Cl. X.R.

